feat: add helpers for extract engine's version

Author: jremy42

internal/services/rdb/helpers.go

@@ -3,6 +3,9 @@ package rdb
 import (
 	"context"
 	"errors"
+	"fmt"
+	"regexp"
+	"strconv"
 	"strings"
 	"time"
 
@@ -100,3 +103,19 @@ func getIPConfigUpdate(d *schema.ResourceData, ipFieldName string) (ipamConfig *
 	}
 	return ipamConfig, staticConfig
 }
+
+func ExtractEngineVersion(engine string) (int, error) {
+	re := regexp.MustCompile(`[-](\d+)`)
+	matches := re.FindStringSubmatch(engine)
+
+	if len(matches) < 2 {
+		return 0, fmt.Errorf("no version found in: %s", engine)
+	}
+
+	version, err := strconv.Atoi(matches[1])
+	if err != nil {
+		return 0, fmt.Errorf("failed to convert version to integer: %w", err)
+	}
+
+	return version, nil
+}

internal/services/rdb/helpers_test.go

@@ -31,3 +31,39 @@ func TestPrivilegeV1SchemaUpgradeFunc(t *testing.T) {
 		t.Fatalf("\n\nexpected:\n\n%#v\n\ngot:\n\n%#v\n\n", v1Schema, actual)
 	}
 }
+
+func TestExtractEngineVersion(t *testing.T) {
+	tests := []struct {
+		engine         string
+		expected       int
+		expectingError bool
+	}{
+		{"postgresql-15", 15, false},
+		{"mysql-8.0", 8, false},
+		{"redis-6", 6, false},
+		{"mariadb-10.5", 10, false}, // Only extracts the major version
+		{"invalid-engine", 0, true}, // No version to extract
+		{"", 0, true},               // Empty string case
+		{"mongodb-3.6", 3, false},   // Extracts only the major version
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.engine, func(t *testing.T) {
+			result, err := rdb.ExtractEngineVersion(tt.engine)
+
+			if tt.expectingError {
+				if err == nil {
+					t.Errorf("expected an error for engine %q, but got none", tt.engine)
+				}
+			} else {
+				if err != nil {
+					t.Errorf("did not expect an error for engine %q, but got: %s", tt.engine, err)
+				}
+
+				if result != tt.expected {
+					t.Errorf("expected version %d for engine %q, but got %d", tt.expected, tt.engine, result)
+				}
+			}
+		})
+	}
+}

internal/services/rdb/instance.go

@@ -18,6 +18,7 @@ import (
 	"github.com/scaleway/terraform-provider-scaleway/v2/internal/locality/regional"
 	"github.com/scaleway/terraform-provider-scaleway/v2/internal/locality/zonal"
 	"github.com/scaleway/terraform-provider-scaleway/v2/internal/services/account"
+	rdbtestfuncs "github.com/scaleway/terraform-provider-scaleway/v2/internal/services/rdb/testfuncs"
 	"github.com/scaleway/terraform-provider-scaleway/v2/internal/types"
 	"github.com/scaleway/terraform-provider-scaleway/v2/internal/verify"
 )
@@ -554,8 +555,13 @@ func ResourceRdbInstanceUpdate(ctx context.Context, d *schema.ResourceData, m in
 	}
 
 	////////////////////
-	// Upgrade instance
+	// migrate instance
 	////////////////////
+
+	//if d.HasChange("engine") {
+	//
+	//}
+
 	upgradeInstanceRequests := []rdb.UpgradeInstanceRequest(nil)
 
 	rdbInstance, err := rdbAPI.GetInstance(&rdb.GetInstanceRequest{
@@ -568,6 +574,22 @@ func ResourceRdbInstanceUpdate(ctx context.Context, d *schema.ResourceData, m in
 	diskIsFull := rdbInstance.Status == rdb.InstanceStatusDiskFull
 	volType := rdb.VolumeType(d.Get("volume_type").(string))
 
+	if d.HasChange("engine") {
+
+		lastEngine, err := ExtractEngineVersion(rdbInstance.Engine)
+		if err != nil {
+			return diag.FromErr(err)
+		}
+		newEngine, err := ExtractEngineVersion(d.Get("engine").(string))
+		if newEngine <= lastEngine {
+			return diag.FromErr(errors.New("volume_size_in_gb must be a multiple of 5"))
+		}
+		engine := rdbAPI.FetchLatestEngineVersion()
+
+	}
+	////////////////////
+	// Upgrade instance
+	////////////////////
 	// Volume type and size
 	if d.HasChanges("volume_type", "volume_size_in_gb") {
 		switch volType {